What to Blog About?

Sorry for the lack of posts lately, but I am trying to decide what direction to go with this blog.  I figured it would be easy, because I could just blog about what I have interest or experience in.  But this is such a broad area, and I am having difficulty narrowing it down.  I have experience in mechanical, biomedical, and electrical engineering.  I work on cars a lot, have the knowledge of a mechanic, and know how to do autobody work and paint cars.  I also have an extensive collection of tools and am constantly building things.  I have a pet bullmastiff that my wife blogs about.  I keep a saltwater reef tank as a hobby, and have various corals.  I designed the lighting and filtration systems for the reef tank myself.  I do secret work at a research institute that I am not allowed to talk about.  I have cut up cadavers for research before.  I have written numerous journal articles, and many more papers and review articles.  I have invented several medical devices, two of which have been patented and are in varied stages of development.  I have designed waste treatment systems for chemical plants, designed mechanical robots for building batteries, designed new age lead-acid batteries, designed glucose testing devices for diabetic patients, helped develop new treatments for early detection of retinoblastoma (eye cancer) in children, and numerous other things, some of which are not patented yet, so I can't talk about them.  These are some of my interests, but I am not sure where to go with it yet in this blog.  I have other blogs as well, and my wife does, so I will try not to overlap too much.  If you have any requests or interests, let me know.  I could share some of my research from grad school or from undergrad as well, if nothing else seems to be of interest.